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Biomedical subjects

Y Ando

Publications and source records attributed to Y Ando.

At least 649 records · Page 36Linked to original sources
PubMed1983

Direct preparation of solid particulates of aminopyrine-barbital complex (pyrabital) from droplets by a spray-drying technique.

Aqueous slurries of aminopyrine and barbital (molecular ratio 2:1) containing various excipients such as colloidal silica, synthetic aluminum silicate, montmorillonite clay, corn starch, microcrystalline cellulose, hydroxypropylcellulose, methylcellulose, gelatin, and chitosan were spray-dried by a centrifugal wheel atomizer with various rotation speeds (10,000-40,000 rpm) at various temperatures (85-145 +/- 5 degrees). The spray-dried products were a mixture of aminopyrine-barbital complex (molecular ratio 1:1), aminopyrine, and the excipient used. The flowability and the packing property of the products were improved by compounding colloidal silica into the formulation used for spray-drying. The products with montmorillonite clay, chitosan, and a corn starch-colloidal silica mixture were compressed directly into tablets. It was found that aminopyrine in the products was oxidized during spray-drying. The oxidation products were assumed to be a trace mixture of 5-oxo-2-methyl-4-dimethylamino-1-phenyl-3-pyrazoline carboxyaldehyde and miscellaneous oxidation products. Montmorillonite clay compounded in the formulation considerably prevented the oxidation of aminopyrine during spray-drying. The present study proposes an improved method for the preparation of solid particulates of aminopyrine-barbital complex for tableting, which combines the synthesis, drying, and agglomeration processes into a single process.

Aerosols↗
PubMed1983

Postnatal changes of cerebral blood flow velocity in normal term neonates.

Postnatal changes of cerebral blood flow velocity were studied in 43 healthy term neonates using a continuous waveform bidirectional Doppler flowmeter and an ultrasonograph with a pulsed Doppler unit. Pulsatility Index (PI) values of anterior cerebral artery were high within 6 hours after birth, and then decreased in the neonates born by means of both vaginal delivery and caesarean section. These postnatal changes of PI observed with the continuous waveform bidirectional Doppler flowmeter were identical with those with pulsed Doppler technique. The sequential measurement of right radial artery blood flow showed a marked decrease of diastolic flow velocity, which may be due to transient postnatal patent ductus arteriosus. Therefore, this postnatal transient patent ductus arteriosus may be one of the pathogenetic factors for high PI values shortly after birth.

Blood Flow Velocity↗
PubMed1983

Cerebral blood flow velocities in postasphyxial term neonates.

Blood flow velocities of the anterior cerebral artery and right radial artery were studied in 15 postasphyxial term neonates using a continuous waveform bidirectional Doppler Pulsatility index (PI) values of most mild asphyxic infants were within the normal range. However, the infants with anoxic encephalopathy showed high or low PI values. The minimal flow velocities of the right radial artery (RRA) showed markedly retrograde flow velocity shortly after birth in comparison with those of the controls. The high PI values may be mainly due to a marked decrease of diastolic flow velocity representing retrograde flow in RRA. The low PI values indicated the poor prognosis in the postasphyxial infants. In low PI cases the cerebrovascular autoregulation may be presumed to be impaired, and arterioles to be markedly dilated.

Asphyxia Neonatorum↗
PubMed1983

Mechanism of chemical manipulation of the heat resistance of Clostridium perfringens spores.

The mechanism of chemical manipulation of the heat resistance of Clostridium perfringens type A spores was studied. Spores were converted to various ionic forms to base-exchange technique and these spores were heated at 95 degrees C. Of the four ionic forms, i.e. Ca2+, Na+, H+ and native, only hydrogen spores appeared to have been rapidly inactivated at this temperature, when survivors were enumerated on the ordinary plating medium. However, the recovery of the survivors was improved when the plating medium was supplemented with lysozyme, and more dramatically when the heated spores were pretreated with alkali followed by plating in the medium containing lysozyme. In contrast to crucial damage to germination, in particular to spore lytic enzyme, no appreciable amount of DPA was released from the heat-damaged H-spores. These results suggest that a germination system is involved in the thermal inactivation of the ionic forms of spores, and that exchangeable cation load plays a role in protection from thermal damage of the germination system within the spore. An enhancement of thermal stability of spore lytic enzyme in the presence of a high concentration of NaCl was consistent with the hypothesis.

Calcium↗
PubMed1982

Computed tomography of malignant tumors of the nasal cavity and paranasal sinuses.

Staging of malignant tumors of the nasal cavity and paranasal sinuses by computed tomography (CT) was studied in a total of 49 patients, 33 with squamous cell carcinoma and 16 with tumors of other histologic types. Involved sites by the tumor were studied, and clinical staging was made using CT findings alone according to AJC classification for maxillary sinus tumors. Surgical findings for comparison were available for most cases. Of 33 squamous cell carcinomas and of 16 tumors with other histologic types, the maxillary sinus was the site of origin in 29 and eight, respectively. Of these 37 maxillary sinus tumors, 11 were staged T3, 26, T4, and none was staged T1 or T2. None of these tumors were down staged, and one T3 was upstaged after surgical procedures, although all sinuses were not explored in some cases. Sinusitis due to obstruction was indistinguishable from the tumor without bone destruction. And the determination of the site of origin was difficult in some cases. Despite these, CT should be used for pretreatment evaluation of the tumors of these sites.

Adenocarcinoma↗
PubMed1982

Detection of hypercoagulability by the measurement of the dynamic loss modulus of clotting blood.

The dynamic loss modulus of clotting whole blood was measured in thrombotic patients to characterize the physical properties of coagulation in the hypercoagulable state. The dynamic loss modulus was measured by a Sonoclot. Thrombotic patients consisted of 30 with deep vein thrombosis and 25 with arterial thrombosis. An accelerated increment rate of the dynamic loss modulus at the beginning of gelling was the characteristic of hypercoagulability. This characteristic occurred more frequently than other abnormalities in other tests for hypercoagulability (beta-thromboglobulin, antithrombin III and TEG). Only in deep vein thrombosis, a moderately positive correlation was noted between the increment rate of the dynamic loss modulus and the plasma fibrinogen level.

Adult↗
PubMed1982

On the mechanism of heparin-induced potentiation of platelet aggregation.

The role of antithrombin III (AT III) in heparin-induced potentiation of platelet aggregation was investigated using purified AT III and AT III depleted plasma. When ADP or epinephrine was added to citrated platelet rich plasma (PRP) one minute after addition of heparin, marked enhancement of platelet aggregation was observed, compared with the degree of platelet aggregation in the absence of heparin. However, heparin exhibited no potentiating effect on ADP- or epinephrine-induced platelet aggregation when platelets were resuspended in AT III depleted plasma prepared by immunosorption using matrix-bound antibodies to AT III. When purified AT III was added to AT III depleted plasma at a concentration of 20 microgram/ml, potentiation of platelet aggregation by heparin was clearly demonstrated. These results suggest that the effect of heparin on platelet aggregation is also mediated by AT III.

Adenosine Diphosphate↗
PubMed1982

Preparations of solid particulates of theophylline--ethylenediamine complex by a spray-drying technique.

Aqueous solutions of ethylenediamine and theophylline were spray dried to obtain solid particulates of theophylline--ethylenediamine complex to improve solubility of theophylline. Packing and flow properties of the spray-dried products were much improved when compared with those of original theophylline particles, due to their spherical shapes which were confirmed by a scanning electron microscope. The solubility of theophylline in the resultant products was found to be three to five times higher than that of original theophylline. The solubilities of the products decreased with increasing drying temperature and rotation speed of the atomizer, which was interpreted in terms of the contents of ethylenediamine in the products. The products were confirmed to be a mixture of aminophylline, alpha-aminophylline, and theophylline by X-ray analysis and NMR spectroscopy. The logarithm of the relative intensity of the X-ray diffraction peak of alpha-aminophylline to that of theophylline decreased linearly with drying temperature and rotation speed of the atomizer. Thermal decomposition of the spray-dried products involved liberations of crystal water at 100 degrees and ethylenediamine between 110 and 127 degrees. Liberation of ethylenediamine occurred via three steps for aminophylline, but with different steps for the spray-dried products.

Aerosols↗